patch 8.0.1654: warnings for conversion of void to function pointer

Problem:    Warnings for conversion of void to function pointer.
Solution:   Use a temp variable that is a function pointer.
diff --git a/src/version.c b/src/version.c
index 791549c..1d9d376 100644
--- a/src/version.c
+++ b/src/version.c
@@ -763,6 +763,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1654,
+/**/
     1653,
 /**/
     1652,